Grass Particle System is Sideways
Select the whole particle object (the one you used to make the particles) in edit mode, and rotate it by 90deg (or -90deg) on one of the axes (whichever one points it &quot;upright&quot;). From here, make sure &quot;Advanced&quot; is checked at the top of your particle settings (so &quot;rotate&quot; becomes an option), and under rotate, move the phase away from the default value. This will rotate them on the z axis, and also allows &quot;randomize phase&quot; to have an effect. Increase the random to get random z rotations.